Torsion recoil spring



DeC 20, 1949 R. K. WINDHAM TORSIQN RECOIL SPRING Filed April 29, 1946 Ruy K Windhnm atented Dec. 20,1949

UNITED STATES PATENT @FFHCE 'l 2,491,539 TORSION RECOIL SPRING Ray K. Windham, Bethesda, Md. Y l Application April 29, 1946, Serial No. 665,715

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) 2 Claims.

invention is the utilization of one or more dis-v tortable elements, such as torsion bars, capable of supporting the moving part and being so distorted by the force of the recoil causing the movement of the part, as to be tensioned to the desired degree to eiect the desired result. Application of my improved mechanism to pieces operating with counterrecoil affords the means for producing thedesired form of counterrecoil.

While I have illustrated in the drawing filed herewith and have hereinafter fully described the structure and operations of one specificV embodiment of my invention, it is to be distinctly understood that I do not consider my invention to be limited to said specific embodiment, but refer for its scope to the claims appended hereto. In the aforesaid specific embodiment I have shown my improved mechanism applied to a submachine gun, such as the standard caliber .45, M3, having the breech bolt reciprocated in recoil and'counterrecoil, but it is obvious that the improved mechanism is equally applicable to any other form of firearm having a part movable by recoil.

In the drawings:

Figure 1 is a longitudinal section of my device, on the line I--I of Figure 2.

Figure 2 is a vertical section on the linev 2--2 of Figure 1 in the direction of the arrows.

Figure 3 is a fragmentary side elevation of the bolt in the direction of the arrow 3 of Figure 2.

Figure 4 is a vertical section on the line 4-4 of Figure 1 in the direction of the arrows.

Figure 5 is a vertical section on the line '5-5 of Figure 1 in the direction of the arrows.

Figure 6 is a vertical section on the line 6-6 of Figure 1 in the direction of the arrows.

Figure 7 is a view similar to Figure 3 showing a modified form of roller jaws for the torsion bars.

Figure 8 is a vertical section on the line 8--8 of Figure 9; showing -a modied form of anchoring means for the torsion bars.

Figure -9 is a vertical section on the line 9 9 0f Figure@ inthe ldirection of the arrows.

As illustrated in the drawing, my improved iirearm is provided with a receiver I having a rear end wall 2, and to the forward end of which a f barrel sleeve 3 has been secured in any suitable way. A barrel A is threadedly engaged with thev internally threaded sleeve 3 by the externallythreaded barrel bushing 5. The receiver I serves as a housing for the bolt assembly which comprises the breech bolt 6 formed with an integral ring pin 1. A pair of bores 8 is provided through the bolt e parallel to its longitudinal axis.

ceived in each bore 8 is a torsion Vbar 9.

and bearings IZb in which are received the reduced cylindrical portions 9d of bars 9 which pass y forwardly of the plate I2 where they have peripheral grooves 9e. The enlarged cylindrical portion 91 of each bar 9 rearwardly of the vplate I 2V provides a shoulder 9g and a spring clip I3 seated in grooves 9e serves to coni-lne the plate I2 loosely against the shoulders 9g. The forwardly extending ends of portions 9d of rods 9 are received in an internal channel 5a of bushing 5, and whenA bushing 5 has been properly engaged with sleeve 3 its inner end 5b is seated against the forward face I2c of plate I2. l y

The bolt 6 is provided with a suitably disposed and configured transverse bore I4 in which is received a block I5 in which are journaled two I pairs of jaw rollers I6. VThe block I5 may be removably mounted in bore I4 and staked in position by countersunk screws I5a threaded commonly in the meeting faces of the bolt 6 and block l I5. The rollers I6 have their pintles Isa journaled in the block I 5 so as to dispose the surfaces of the rollers I6 of each pair suiflciently relatively spaced to contact the opposite faces, respectively,'of the 'flattened portion 9h of one of the bars 9. As illustrated in Figures 2 and 3, the rollers I6 are so mounted in block I5 that their longitudinal axes lie in the same plane which is parallel to the sides of the block I5. In Figure rI another arrangement of the rollers is illustrated in which the roller IIb on the near side of bar 9 inclined rearwardly andthe roller IBc on the Re- The rear ends of the bars 9 are non-rotatably mountedin a' plate le provided with slots I I through which passv the flattened end portions 9a of bars 9. Shoulders The forward ends of the bars 9 are rotatably journaled in a plate I2 having keys I2c received in keyways 3a in barrel sleeve ,3,

far side of bar 9 is inclined forwardly. It is to be understood that the pair of rollers co-acting with the other bar 9 is also inclined but in the reverse relation.

As illustrated in Figure 1, the bolt 6 is disposed forwardly in receiver I, its firing pin 1 in operative engagement with the percussion cap of the cartridge C in the chamber I'I ofv barrel 4 they forward end 9a of the bolt 6 contacting theY rear. face of plate I2. When the bolt 6 is in this position, the cylindrical portions 9f of the bars 9; extend through bores 8 in bolt 6 rearwardlyfroln the plate I2 to that portion of the boltjlimrne-` diately forward ofthe block I5 carryingtherollers I6, to afford support for the bolt Il,n lc'learwardly of the rear ends 9i of the cylindrical portionsr 9j; the attened portions 9h. extend between. the rollers I6 and to the rear end portions 9d, anchored as above described." As,` illustrated in` Figures 1 and 6, the flattened end portions 9a are' disposed substantially horizontally and asrilluestrated in Figures 1, 2;' 3 and?, the forward ends o'f the flattened portions 9hypassed between the rollers 'I6 are Ydisposed?substantially vertically, causing the Vflattened.'portions l9h. to have a 90 twist between the plater I9 and the rollers I6. It Will'be noted (Figure 1) thattheseftwistsv areoppos'itel'y directed.

In Figures 8 and 9 there is illustrated a modied form of anchoring means for the bars 9, In this form, the receiver I'I'l hasfa 'removable rear end wall'IIlZ attached to the receiver II by bolts ID3. A plate I I9 is providedwhich has suitable bores I I Itherein with radial key'ways lI I2, and-in which are received, Yrespectivelvfsockets II3 having radial keys IIII 2o-acting with keyways II2,` and slotsv H5 tolreceive therein the attened ends 9a ofthe rods 9. The Vplate II has bores IIB in which are received'thel ends of bolts |93 to correctly position'rodsll in receiver IUI.

From the foregoing descriptionoflthe details of constructionof myimproved firearm its use and operation will be obvious. The'partsare assembledby'inserting bars 9 intobores 8 at the forward end of bolt'iA and passing the flattened portions l 9h" of bars 9 between the'rellers 'which have beenmountedin bolt by mounting block` I5 in boreIlII'. The'fiattened'portions Saare then in-e, serted in slots II of plate Ilcare bein'ghajd' that thebars 9 be reversely twisted. The plate I`2 isA thel'placed on the forvvaid endsof bars9, the

' into the receiver IDI through its opened rear end.

the receiver I. After the parts have been dis;`

posedin the receiver I, the bushing'is engaged. with sleeve 3, and the parts are inlthe ip ositions illustrated in Figure 1.

When the modified form of anchoringmeansA` illustrated in Figures 8 and 9 is used, thedegreen of the initial twist of the bars. 9 can be detfermirred.;`

nicely bythe adjustment of Asoclrejssl Il 3 ,in bores; IIIVof plate H9. After the ends9 a has/e5been` inserted in slots II5 of the socketsvIIH-Sjthebars Scan be twisted to they desiredgdegreeby r tion of sockets II3 and Ywhen thesocketsJIS pieces in bores I l I of plate" l lalnidkeysl ,lip-rg.,

76 and second torsionrodsinsaid receiven. ca h'rid'.

Firing of the cartridge C by the firing pin l projects the bullet B through the barrel 4, and the blowback drives the case of the cartridge C rearwardly causing the bolt 6 to travel rearwardly on its supportingV bars 9. As the jaw rollers I6 carried by the bolt 6 travel rearwardly over the flattened portions 9hl of bars 9, they exert a twisting moment on the bars 9 since the rear ends 9a of the bars 9 are anchored to prevent rotation and the forward ends 9d of bars 9m arenjournaled tofpermit rotation. YDueto the fact thatthe in ifal.v twists of the bars 9 (Figure 1') are oppositely'directed, the respective twisting moments, offthey pairsof rollers I9 areoppositelyfdirected. This distortion. 0f bars 9. Callsedby the reQQilf 5.91?. 6 .builds up the requisite tensin in bars U0 .p'ni duce the. @.Ounerreeol '0f holt 6.. whenftlie. farce. 0f threcqil hasberlpent and th-bd@ EgiS- returned to battery, as shownin' Figure 1 Just'I asthe force ofthe recoil drivesbolt,6,rearwardly` and .Causehe rollers, ILMQDYQSS' upgnihebasl S1.. andr twist thelbars 9so 'the'force of,` the tx nj 0f thetwsted. bars 9. causes. thebesfltpp against the lollersAV L6. and drive the 'blt' vim?. Wardly. if! CQunfreCQl- With the dspositioik ofn rollers IIb and I6c, illustrated infFi'gure'Y," there is a forward component inthisaction.'as?.4 sistmg in drivingthe boit stehen-ery;

Itis to be understood that the partsvpareso.. related than when the bolt vIlV has recoiledstoits'" rearwardllimit of movement, putting. the bars@ undertheir maximum tension, theforwardfend.; of the'bolt Bgis forward of therear :grids-191'?,ff,"V theynndricaiporiions sf @rachats-.9..sustain.. the boit s islconstantly,suppcrted'pyguie "p ort 'nel 9j inbores 8 at 4its forwardndlnd bythe;l pre end, thus insuring proper, Ieciprocalon fof. bolt-IiW in kboth recoil and counterrecoil. navnadgsribed. my.- nYGmQn what: I Claim- 1, In a firearm, areceiver, a,bolt..reciprocablei insaid receiver and having apair ofv spaced-1321.15!` allel boresparallel to the direction'.of".'recoil-and counterrecoil of saidbolt, first. and'.'s'lecond torsion rods inA said receiver, each passing/through are- Speti'verlef; Said .borseahlrd comifisiaa forward Cylindrical `portionv fitting its'. respective bore, and a'rearwardlflatpqrtim, means.-.carri'ed by saidv receiver journaling?saidirodsattheir fore. ward ends, means Iat,the` rear, endof 'said {receive-r. fixing the rearends'of eachmflat portion'. aga t?. rotation, `said rods,` beingA initially roppos y' stressed in tfofrsion, and twdpairs' of.rollers iouii-NA` nalled in ,said'bolt on spacedparallel.axisllolml to the direction` ofrecoil.and.counterregoilof'Y said bolt, the rollers of each 119.19., beim; spaced 'GO reeive' the flat perionof. a respective wisse bar between them. v

2- Anautomaticrearm compri-.Sing a retener, a bflll rciprucable, instill rece. ,l mere-being@ pair of spaced bores in said bolt. arallel,with'the` direction Qf. relandguriter. withered,

comprising a forward cylindrical portion having a smooth t in a respective bore, and a rearward strap portion, means fixed with said receiver journaling the forward ends of said rods, means rigid with said receiver at the rear end of said rods fixing the ends thereof againstl rotation relatively to said receiver, there being a diametrical bore in the rearward portion of said bolt, a block slidably iitting said bore and having openings through which the strap portion of a respective rod passes, first and second pairs of rollers journaled in said block on axes transverse to the direction of recoil and counterrecoil of said bolt, the rollers of said rst pair engaging respective flat sides of said rst rod and the rollers of said second pair engaging respective at sides of said second rod, all said rollers lying substantially in a plane transversely of said rods, said strap portions being equally and oppositely twisted between the rear end of said receiver and said rollers, whereby increased torsion in said flat portions is effected in response to rearward translation of said bolt.

RAY K. WINDHAM.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS v Date Number Name 350,695 Pattin Oct. 12, 1886 1,077,873 Dawson et al Nov. 4, 1913 1,359,045 Fisher Nov. 16, 1920 1,396,832 Graham Nov. 15, 1921 1,846,035 Larrson et al. Feb. 23, 1932 2,321,592 Green et al. June 15, 1943 FOREIGN PATENTS Number Country Date 144,097 Austria Dec. 27, 1935 

